Reactive extraction of lactic acid using alamine 336 in MIBK: equilibria and kinetics

Abstract

Lactic acid is an important commercial product and extracting it out of aqueous solution is a growing requirement in fermentation based industries and recovery from waste streams. The design of an amine extraction process requires (i) equilibrium and (ii) kinetic data for the acid-amine (solvent) system used. Equilibria for lactic acid extraction by alamine 336 in methyl-iso-butyl-ketone (MIBK) as a diluent have been determined. The extent to which the organic phase (amine +MIBK) may be loaded with lactic acid is expressed as a loading ratio, z=[HL](o)/[B](i,o). Calculations based on the stoichiometry of the reactive extraction and the equilibria involved indicated that more lactic acid is transferred to the organic phase than would be expected from the (1:1) stoichiometry of the reaction. The extraction equilibrium was interpreted as a result of consecutive formation of two acid-amine species with stoichiometries of 1:1 and 2:1. Equilibrium complexation constant for (1:1) and (2:1) has been estimated. Kinetics of extraction of lactic acid by alamine 336 in MIBK has also been determined. In a first study of its kind, the theory of extraction accompanied by a chemical reaction has been used to obtain the kinetics of extraction of lactic acid by alamine 336 in MIBK. The reaction between lactic acid and alamine 336 in MIBK in a stirred cell falls in Regime 3, extraction accompanied by a fast chemical reaction occurring in the diffusion film. The reaction has been found to be zero order in alamine 336 and first order in lactic acid with a rate constant of 1.38 s(-1). These data will be useful in the design of extraction processes.

Recovery of Formic Acid by Reactive Extraction Using an Environmentally-Friendly Solvent

“…However, at the same extractant levels and higher FA concentrations, the z values varied between 1 and 2, indicative of the simultaneous presence of 2:1 and 1:1 type acid-amine complexes. The results are consistent with those reported in the literature for tertiary amines and carboxylic acids (Tamada et al, 1990;Wasewar et al, 2002;Qin et al, 2003;Uslu, 2009;Martı et al, 2011) CONCLUSION Solvent or diluent type used during reactive extraction is so important for the recovery of carboxylic acids (Kertes and King, 1986). However, the most effective solvents are generally toxic chemicals and this is the most critical disadvantage of the technique that prevents its widespread use in industries.…”

Lactic Acid Production to Purification: A Review

“…Approximately 40% to 70% of operating and capital costs are associated with the separations steps (Wankat 2007). In lactic acid production processes, development of an effective method of lactic acid separation and purification from fermentation broth is extremely important for economic viability.…”

“…Otherwise, the separation steps are widely discussed in literature, such as precipitation (Rauch et al 1960;Min et al 2011;Kwak et al 2012;Nakano et al 2012), solvent extraction (Malmary et al 2000;Wasewar et al 2002;Matsumoto et al 2003;Yankov et al 2004;Alkaya et al 2009;Krzyzaniak et al 2013), membrane separation processes, and others. Membrane separation processes that have been studied include reverse osmosis, electrodialysis, and ultrafiltration (Kim and Moon 2001;Choi et al 2002;Madzingaidzo et al 2002;Li and Shahbazi 2006;González et al 2008;Ecker et al 2012;Lu et al 2012;Ramchandran et al 2012;Sikder et al 2012;Dey and Pal 2013;Pal and Dey 2013;Wang et al 2014).…”

Influence of Residual Sugars on the Purification of Lactic Acid Using Short Path Evaporation

“…Therefore, development of an efficient and low-cost separation process is very important, as this can reach up to 50% of the total cost (Wasewar et al 2002;Datta and Henry 2006;Chanukya et al 2013).…”